1. Field of the Invention
The present invention relates generally to a liquid crystal display device, and more particularly, to an arrangement for connecting a flexible printed circuit board to a liquid crystal display device.
2. Description of the Related Art
A liquid crystal display device, which is a typical example of a flat-screen display device, includes a liquid crystal display panel having a liquid crystal layer held between an array substrate and a counter substrate using a seal member. The liquid crystal display panel includes an active area which is composed of matrix-arrayed pixels. The liquid crystal display devices are widely used as display devices for various kinds of equipment such as personal computers, OA equipments, and TV sets because the display devices have many advantages such as lightness, compactness and low power consumption. In recent years, the liquid crystal display device is also used in a mobile terminal equipments such as a mobile phone, a car navigation device and a game player.
Japanese laid open patent application 2006-163100 discloses one example of a liquid crystal display device having a liquid crystal display panel, a flexible printed circuit board and a back light unit housed in a case. Specifically, a flexible printed circuit board is drawn out of slits formed on the rear surface of the bottom of the case and fixed on the rear surface by folding at least twice to form double layers. The folded flexible printed circuit board is fixed by engaging some protrusions formed on the rear surface of the bottom of the housing case with apertures formed on the surface of the flexible printed circuit board. Furthermore, the flexible printed circuit board is adhered by a double faced adhesive tape that is provided on the extended-out portion of the flexible printed circuit board.
As described-above, though the Japanese laid open patent application discloses a technique to implement a long flexible printed circuit board compactly, the total thickness of the module increases due to the expansion of the folded portion of the flexible printed circuit. The length of the flexible printed circuit board varies according to the specification of the equipment provided with outer circuits to which the flexible printed circuit board is connected. Accordingly, in case that further compactness of the module, that is, a shorter flexible printed circuit board to be drawn out is required. It may be thought to fold more times the flexible printed circuit board, however, which results in more increase of the total thickness of the module.